Light level is the amount of illumination that a certain block receives. Light level is rated from 0 to 15, where 0 is pitch blackness and 15 is regular sunlight.
Many objects emit light, and these have a light rating too to tell you how much they illuminate the block they are placed on. Glowstone, Fire, Jack-o-lanterns for example are the same as sunlight, 15. Torches are 14, 'activated' Redstone Ore is 9, Redstone Torches are 7, etc. For each block you move away from a light source, the light rating goes down by 1. If a torch is two blocks away from you therefore, the block you are stood on has a light level of 12.
Light levels affect various things. Light of 13+ will uproot mushrooms. Sunlight of 12+ (so direct sunlight and up to three blocks into the shade) will burn Zombies and pacify Endermen, etc.
no
Make sure that the light level is above 7, and that there is grass near the spawner.
A dungeon in Minecraft can spawn on any level that normal land can spawn on
Mycelium is the equivalent of grass in a Mushroom Island biome. Mushrooms can be planted in it, they can grow even if the light level is too high.
The highest enchantment level in Vanilla Minecraft is level 30 through the use of bookshelves surrounding an enchantment table.
Yes. Slime spawns on swamp biomes on levels 51 through 69, at light level below 8
They need to be supplied with a charge. You can light them by placing a redstone torch on an adjacent block, or you could link them with redstone dust to a lever, the level will provide a charge when 'on' and light the lamp.
The highest level of the sun in Minecraft is 12:00 PM, which is during the afternoon. (It is the same thing in reality, too!)
no you cant
Yes
Protection 1 in Minecraft simply 'ups' the level of damage absorbed by your armor.
i think its y=0?